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European Journal of Wildlife Research

, Volume 62, Issue 2, pp 151–160 | Cite as

Complementary use of density estimates and hunting statistics: different sides of the same story?

  • Eeva M. Soininen
  • Eva Fuglei
  • Åshild Ø. Pedersen
Original Article

Abstract

The use of hunting statistics for population monitoring has often been criticized because such data are affected by several sources of error. Still, for many harvested populations, hunting statistics are the only available data source and cautious use of such data may be valuable for management. Here we assessed to what extent long-term monitoring of Svalbard rock ptarmigan spring densities and hunting statistics (bag size and proportion of juveniles in the hunting bag) reflect similar population fluctuations. We found a decreasing trend in both bag size and proportion of juveniles in the bag, but no trend in ptarmigan spring densities. However, annual fluctuations of ptarmigan spring density and bag size were correlated. Together, these time series indicate that both population abundance (bag size) and recruitment (proportion of juveniles in the bag) are decreasing, but the reproductive component fraction (density of territorial males) is not yet compromised. This biological interpretation remains, however, uncertain due to lack of hunting effort data. Monitoring programs using hunting statistics should therefore critically discuss and evaluate what the hunting statistics reflect and fine-tune the hunter data collection to obtain maximum biological relevance. Still, our results illustrate that the combination of population estimates and hunting statistics can provide more nuanced information about the population status than the density estimates alone.

Keywords

Harvest Lagopus muta Long-term monitoring Point transect sampling Time series 

Notes

Acknowledgments

We thank all field assistants who have participated in the annual monitoring of the Svalbard rock ptarmigans, especially Marie Lier, Heli Routti, Øystein Overrein, and Nina A. Seifert; the Governor of Svalbard for collecting the hunting statistics, especially the Nature Management advisors Bjarte Benberg and Egil Movik; Audun Igesund and Oddveig Øien Ørvoll for graphical assistance; Gunn-Sissel Jaklin for reviewing the English language; and Arnaud Tarroux for guidance to GIS in R. Rolf Ims, Arnaud Tarroux, Øystein Overrein, and three anonymous reviewers gave helpful comments on the manuscript. Personnel costs were provided by the Fram Centre COAT initiative and the Norwegian Polar Institute. Funding for field work was provided by grants from the Amundsen Center of Arctic Research (The Arctic University of Norway), the Governor of Svalbard, the Norwegian Polar Institute, and the Svalbard Environmental Protection Fund.

Compliance with ethical standards

Ethical statement

The hunting of Svalbard rock ptarmigans comply with the regulations in The Svalbard Environmental Protection Act. This article does not contain any studies where human participants or animals were manipulated by any of the authors.

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.UiT The Arctic University of NorwayTromsøNorway
  2. 2.Norwegian Polar InstituteTromsøNorway

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